The present invention relates to a complex system including intelligent work stations and host computers (to be simply referred to as "hosts" herebelow) connected by a micro main frame connection therebetween, and in particular, to a distributed interactive processing method suitable to distribute the load on the hosts to the intelligent work stations (referred to as "IWS's" herebelow).
In an interactive processing system such as the time sharing system (TSS), for the user's request issued from a terminal equipment, the syntactical check has been effected on the terminal side as described in the JP-A-60-144839. However, the request itself is analyzed in the virtual address space of a host computer to select a program satisfying the request in the same space. The selected program first arranges the necessary environment, for example, allocates file and effects an OPEN processing thereon, and then executes the requested processing.
Although the TSS is suitable for an irregular job including various kinds of data, the processing is attended with a large overhead and the number of terminals to be simultaneously supported is limited. The TSS of this kind has been well known. For example, refer to Watson, R. W. "TSS Design Concepts" McGraw Hill Computer Science Series McGraw-Hill Book Co. NY. 1970.
In the transaction processing system (on-line system), a request is issued from a terminal in a small unit called a transaction to a host computer. A transaction executes a processing in accordance with the request in a fixed fashion in a space where the pertinent environment is arranged in advance.
In the transaction processing system, the processing is effected in the unit of transaction, namely, in an intermittent manner and in a fixed fashion. Consequently, this system is suitable for use with an automatic banking machine and the like of a bank; however, the transaction processing system is not suitable for an irregular job including various kinds of unfixed data.
In other words, as shown in FIG. 8, regular job requests supplied from a great number of terminals, for example, several thousands in number are processed in a fixed fashion. The host is provided with a data communication program to be effected by a terminal control section and job programs each for achieving a regular or fixed job and an input from a terminal is processed by a job program structured for a fixed purpose.
In the TSS, as shown in FIG. 9, request indications inputted from a relatively small number of terminals i.e. about 100 in number are received in a logical space disposed for each terminal and is subjected to a request analysis, and then a processing program is loaded for execution. In the host, there are provided a terminal control program, a request analysis program to analyze requests from the respective terminals, and processing programs corresponding to the respective requests. Since the request analysis program and the processing programs are prepared for each terminal, the TSS is suitable for an irregular job handling various kinds of data.
In the TSS and the transaction processing system, a terminal is assigned to a host computer and cannot be easily allocated to be commonly or randomly shared among a plurality of host systems.
In the TSS of the conventional technology, although the syntactical check may be considered to be achieved in a terminal equipment, the request analysis cannot be implemented therein; consequently, there is provided a process (virtual address space) for each terminal to execute programs therein, namely, the request from a terminal is analyzed in the space and the processing environment is established in the same space, thereby executing a processing associated with the request. As a result, although the TSS is suitable for the irregular job to process various kinds of unfixed data, a large load is imposed on the host, which therefore cannot simultaneously process the requests from many terminals.
Furthermore, in the transaction processing system, there does not exist a connection between a terminal and a particular process (space) of the host computer, namely, there is not allocated a processing space dedicated to each terminal, and a routine or regular processing is effected in an intermittent fashion. Consequently, the load on the host can be reduced; however, irregular requests cannot be freely processed in the transastion processing system.
Moreover, in a system including a plurality of host computers, a terminal is required to be connected to a particular host before starting an interactive processing, which leads to a problem that terminals cannot concurrently and arbitrarily access a plurality of hosts for the services thereof.